Washington, D.C. -- Three people familiar with the decision say President Barack Obama is preparing to nominate a former Bush administration official to head the FBI.

The sources say Obama plans to nominate James Comey, a former deputy attorney general under President George W. Bush.

The three people spoke on condition of anonymity Wednesday because they were not authorized to discuss the selection ahead of Obama's announcement.

Comey became a hero to Democratic opponents of Bush's warrantless wiretapping program when Comey refused for a time to reauthorize it. Bush revised the surveillance program when confronted with the threat of resignation by Comey and FBI Director Robert Mueller.